"57" based on a modern production Shure SM57 dynamic mic.
"70" based on a Microtech Gefell UMT70S condenser mic.
"121" based on a Royer R121 ribbon mic.
"160" based on a Beyerdynamic M160 ribbon mic.
"414" based on an AKG C414B-ULS condenser mic.
"421" based on a vintage Telefunken MD421 dynamic mic.
"MID" based on a mid field placed AEA R92 ribbon mic.
"REAR" based on a vintage Neumann KM84 condenser mic.
"ROOM" based on a vintage Neumann KM84 condenser mic.